From 98f73630f96f1a6d8c845b8b3e5f9ae532cf82d1 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 31 Oct 2013 11:19:42 +0100 Subject: [PATCH] KVM: x86: emulate SAHF instruction Yet another instruction that we fail to emulate, this time found in Windows 2008R2 32-bit. Reviewed-by: Gleb Natapov Signed-off-by: Paolo Bonzini --- arch/x86/kvm/emulate.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 8e2a07b..16c037e 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3296,6 +3296,18 @@ static int em_cpuid(struct x86_emulate_ctxt *ctxt) return X86EMUL_CONTINUE; } +static int em_sahf(struct x86_emulate_ctxt *ctxt) +{ + u32 flags; + + flags = EFLG_CF | EFLG_PF | EFLG_AF | EFLG_ZF | EFLG_SF; + flags &= *reg_rmw(ctxt, VCPU_REGS_RAX) >> 8; + + ctxt->eflags &= ~0xffUL; + ctxt->eflags |= flags | X86_EFLAGS_FIXED; + return X86EMUL_CONTINUE; +} + static int em_lahf(struct x86_emulate_ctxt *ctxt) { *reg_rmw(ctxt, VCPU_REGS_RAX) &= ~0xff00UL; @@ -3790,7 +3802,8 @@ static const struct opcode opcode_table[256] = { D(DstAcc | SrcNone), I(ImplicitOps | SrcAcc, em_cwd), I(SrcImmFAddr | No64, em_call_far), N, II(ImplicitOps | Stack, em_pushf, pushf), - II(ImplicitOps | Stack, em_popf, popf), N, I(ImplicitOps, em_lahf), + II(ImplicitOps | Stack, em_popf, popf), + I(ImplicitOps, em_sahf), I(ImplicitOps, em_lahf), /* 0xA0 - 0xA7 */ I2bv(DstAcc | SrcMem | Mov | MemAbs, em_mov), I2bv(DstMem | SrcAcc | Mov | MemAbs | PageTable, em_mov), -- 2.7.4